Ingrown meanders occur when this incision of the river is slow and thus lateral erosion also occurs. This creates an asymmetrical cross-valley shape.
Entrenched meanders have a symmetrical cross section as a result of rapid incision into the bedrock; vertical erosion dominates and thus the valley has a steep gorge-like appearance.
These adjustments by the river to the new base level is known as river rejuvenation as the river attempts to restore its long profile.
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